The present invention relates to a knife for cutting paper or synthetic resin sheets, and is more particularly concerned with improvements in a magazine type knife having a magazine in a main body for storing a plurality of blades for subsequent use.
Hitherto such knives have been known, but each of them has presented some disadvantages in its use as follows:
(1) Blade Body Direct Insertion Type PA0 (2) Magazine Type with which disassembling cannot be performed, and an elastic body is incorporated inside the magazine. PA0 (3) Magazine Type with which disassembling cannot be performed, and an elastic body is outside the magazine. PA0 (4) Magazine Type with which assembling can be performed, and an elastic body is incorporated inside the magazine. PA0 (5) Magazine Type with which assembling can be performed and an elastic body is incorporated outside the magazine.
Knives of this type allow the direct insertion of a plurality of blade bodies into a main knife body at the same time, as disclosed, for instance, in Utility Model Application laid open No. 52-72200.
With the knives of this type, insertion of the blade bodies is extremely difficult due to the fact that insertion has to be performed against elastic pressure since an elastic body is installed in the main body.
With knives of this type, a magazine storing a plurality of blade bodies is fitted inside the main body, and is constructed so as not to be disassembled. An elastic body pressing against the blade bodies is installed inside the magazine. These types were initially designed so that the magazine is disposable. However, the magazine can be refilled with new blade bodies by a user, as disclosed, for instance, in Patent Publication No. 50-8840, Utility Model Publication No. 53-44800 and Utility Model Publication No. 54-16880.
With knives of this type, just as with the knives of the Blade Body Direct Insertion Type, insertion of the blade bodies is extremely difficult due to the fact that insertion has to be performed against an elastic body incorporated inside the magazine.
With knives of this type, a magazine storing a plurality of blade bodies is fitted inside the main body, and is so constructed that it cannot be disassembled. An elastic body to press the blade bodies is installed in the main body. Such magazines are normally designed to be disposable. However, the magazine can be refilled with new blade bodies by a user, as disclosed, for instance in Utility Model Publication No. 57-51010.
With knives of this type, insertion of blade bodies is easily performed since there exists no elastic body. However, due to the fact that an elastic body does not exist, blade bodies are not kept secured but float inside the magazine until it is fitted to the main body, thus resulting in possible damage to the edge portions of the blade bodies.
With knives of this type, a magazine storing a plurality of blade bodies is fitted inside the main body. The magazine is initially so designed that it can be disassembled and refilled with a plurality of new blade bodies at the same time by a user, as disclosed, for instance, in Utility Model Application Laid Open Nos. 48-94299 and 50-64100.
With knives of this type, insertion of blade bodies can performed with ease, but the components of a magazine might be easily misplaced or assembly can be wrongly done by a user.
With knives of this type, a magazine storing a plurality of blade bodies is fitted inside the main body, and is so constructed that it can be disassembled. An elastic body to press the blade bodies is installed in the main body. The magazine is initially so designed that it can be disassembled and refilled with a plurality of new blade bodies at the same time by a user, as disclosed, for instance, in Utility Model Publication No. 52-4640.
With knives of this type, insertion of blade bodies can be performed with ease, while the components of a magazine might be easily misplaced or assembly can be wrongly done by a user, and possible damage of the edge portion of the blade bodies might be caused because each blade body is not kept secured but floats inside the magazine until it is fitted to the main body.
As aforementioned, in conventional knives, there have been advantages as well as disadvantages.